Asphalt plants and the technologies associated therewith are a necessary component of the various industrial apparatus needed to supply the demands of today's society, including paving for highways, parking lots, and the like. Unfortunately, the ingredients of the materials involved and the high temperatures required to properly process those materials are a source of air borne particles, gaseous substances and vapors that are not only noxious and contaminating, but are the source of odors which can create a substantial nuisance.
By regulation, the contaminating aspects must be reduced below certain levels and various types of apparatus and processes have been developed to meet these requirements. Unfortunately, even as those regulations are satisfied, residual amounts of the contaminants at those environmentally acceptable levels still produce fumes and odors which create a nuisance, primarily due to minute sources of leakage at various transition points between the various components of the asphalt plant as asphalt materials are conveyed therethrough. For example, as processed material is transferred from a dryer/mixer to a conveyor, from a conveyor to a batcher, from a batcher to a silo, or from a silo to a truck for transportation to a construction site, odors escape into the ambient atmosphere. A major source of the release of these nuisance odors to the atmosphere at the transition points arises from the failure to provide for the displacement of air and other gases and vapors within the various components of the plant to make way for the solids being transferred, and/or failure to provide for fluid filling of a void being created behind such solids during such transfer. As a result of the nuisance created by the leakage of the fumes and odors, even though at environmentally acceptable levels, the placement of an asphalt plant relative to other activities and developments in the surrounding area is sometimes very limited.
What is needed is a gas containment system which provides for displacement of air and other gases and vapors during transfer of asphalt material within an asphalt plant in such a manner that such air and other gases and vapors are prevented from escaping into the surrounding atmosphere and, further, to provide a fluid source for filling voids created behind the asphalt material as it is being transferred with such air and other gases and vapors.